The Patient and Clinician Assessment of Gastrointestinal (GI) Related Adverse Events Associated with Oral Disease-Modifying Therapies in Multiple Sclerosis: A Qualitative Study

Abstract

Introduction: Current guidelines for relapsing-remitting multiple sclerosis (RRMS) call for treatment with disease-modifying therapies (DMTs) early in the disease to prevent relapses and accumulation of neurologic impairment and disability. However, patients taking certain oral DMTs may experience gastrointestinal (GI)-related adverse events (AEs), particularly at dose titration. We conducted qualitative research with healthcare professionals (HCPs) and patients in Canada to contextualize their experiences with three oral DMTs: dimethyl fumarate (Tecfidera^®), fingolimod (Gilenya^®), and teriflunomide (Aubagio^®). The objectives of this study were to (1) gather qualitative data to better understand the patient and HCP experience of GI AEs in oral MS DMT treatment in Canada and (2) determine to what extent two patient-reported outcome (PRO) instruments used in recent oral DMT trials capture what is important to patients regarding GI AEs in oral MS DMT treatment (content validity) and to provide qualitative data to help interpret PRO scores.

Methods: This was a qualitative, non-interventional, descriptive, cross-sectional study comprising HCP and patient interviews conducted in English and French, using a 1:1 semi-structured interview approach.

Results: Patients reported 16 unique GI AE concepts related to oral DMTs. The most commonly reported symptoms were diarrhea, indigestion, and nausea. While patients acknowledged the negative impact associated with GI-related AEs, most characterized the treatment experience as positive, focusing on preference for oral administration, perceived efficacy of DMTs in terms of lack of MS relapses, slowed progression of their disease, and improvement in MS symptoms. Results supported the content validity (relevance, comprehension, and comprehensiveness) of the two PROs assessed. HCP feedback reinforced patient perspectives on both GI concepts and the two PRO instruments.

Conclusion: Outcomes of these research activities include experiential data on the symptom and impact experience of oral DMTs in MS from both patients and HCPs that contribute to the process of determining therapeutic value.

Keywords: Dimethyl fumarate; Diroximel fumarate; Disease-modifying therapy; Gastrointestinal tolerability; Multiple sclerosis; Patient preference; Patient-reported outcome (PRO); Tolerability.